A lot of parents contact me to discuss how much time their teen spends talking to their friends, online or in person, at all times of day or night. Whether it's during meal times, or checking for messages overnight, they tell me their teen is 'obsessed' with their friends, sometimes to the exclusion of all other activities.
Well, my fun fact is this!
The teenage brain is actually designed to focus a laser-like beam on to their 'peer relationships' (friends) as part of their growth, development and life skills, to ensure that they are 'part of a tribe' and not isolated, as a human.
Building very strong peer connections is a survival technique, developed over millennia, and not one we are likely (as their parents) to overcome- so we need to work with it!
Their friends will seem literally more important than their family (BUT they don't love them more than you, they just want to be completely focussed on their friends- and strengthen their bonds with them more than they need to with you!). This will ensure their 'survival' outside the family nest in future, by building their safety net of friends in adolescence.
This might even explain why they are prepared to take more risks to be with their friends now in the middle of a pandemic, when we oldies are all at home being careful! Their social network is literally more important to them than almost anything else in teen and young adulthood.
So maybe this answers some of the 'why' questions about why they call or message their friends when they have only just said goodbye to them at school or why they want to spend time with them rather than you (in real or online life).
Understanding just how important (and subconscious) this pull towards friends is may mean that you can have more helpful or informed conversations with them, and avoid rows, so that compromise and negotiation can take place- for example about phone use, going to parties, or maintaining physical distancing...
I hope this helps and gives you a new insight, or angle, on future conversations with your teen!